Although automatic shut-off liquid dispensing valves and devices are known, both in the art of gasoline tank filling nozzles which are very rugged and relatively insensitive and heavy as shown by Payne U.S. Pat. No. 1,725,826 issued Aug. 27, 1929; Frank U.S. Pat. No. 2,309,503 issued Jan. 26, 1943; Rhodes U.S. Pat. No. 2,595,166 issued Apr. 29, 1952; Fromm U.S. Pat. No. 3,208,486 issued Sept. 28, 1965; and Giger U.S. Pat. No. 2,402,036 issued June 11, 1946, and in the art of battery-filling devices as disclosed in Williams U.S. Pat. No. 2,822,831 issued Feb. 11, 1958 and Stoner U.S. Pat. No. 3,957,093 issued May 18, 1976. Also several of these patents disclose mechanisms including toggles which are employed for controlling their valves for dispensing liquid. However, no one or combination of these references discloses applicants' specific combination of features, or applicants' two-part manual plunger means and its dual functions of automatic control and overriding ability. Furthermore, applicants' dispenser is made of rigid lightweight acid-resistant materials which add to its sensitivity of operation and durability for use with acid and electrical equipment without hazard or deterioration.